The government of Colonel Muammar Gaddafi's has said it is is ready for immediate negotiations with rebels seeking to oust him.
The regime has called on NATO to convince the rebel forces to halt an attack on the capital, Tripoli.
In an unexpected press conference tonight, spokesman Moussa Ibrahim said Gaddafi was prepared to negotiate directly with the head of the rebel National Transitional Council.
He added that 1,300 people had been killed in fighting in Tripoli today.
Libya's rebel fighters will halt their offensive if Gaddafi announces his departure, the head of the National Transitional Council said on Al Arabiya television.
Mustapha Abd El Jalil added that the rebel forces would give Gaddafi and his sons safe passage out of the country.
The rebels are said to be closing in on the centre of the city.
The convoy appeared to meet little or no resistance from Colonel Muammar Gaddafi's forces, according to witnesses.
The rebels fired guns into the air in celebration near the neighbourhood of Hay Andaluf.
A Reuters journalist saw thousands of rebels advancing toward Tripoli earlier in the day on the coastal highway from the west.
Earlier, a Libyan rebel official claimed that victory was imminent for the rebels.
Speaking to reporters in Dubai, the National Transitional Council's envoy to the United Arab Emirates, Aref Ali Nayad, also said the rebels had made a formal request for NATO to join the final battle with Apache assault helicopters.
He said the battle for Tripoli has left hundreds dead and thousands wounded.
NATO has described the situation in Libya as 'very fluid', and added that the rule of Muammar Gaddafi was 'crumbling'.
'It's a very fluid situation. We can see that the regime is crumbling, and the sooner Gaddafi realises he cannot win this war against his own people, the better,' NATO spokeswoman Oana Lungescu said.
'He's the one who's responsible for starting the conflict and he should spare his people further bloodshed,' she added.
Gaddafi issues rallying call
Gaddafi today urged Libyans to take up arms and crush the uprising in Tripoli as rebel troops closed on the capital for a final onslaught on his stronghold.
‘I am afraid if we don't act, they will burn Tripoli,’ he said in an audio address broadcast on state television. ‘There will be no more water, food, electricity or freedom.’
Thousands of rebel fighters 25km west of Tripoli were moving towards the capital this evening. As they advanced, they took control of a barracks belonging to the Khamis brigade, an elite security unit commanded by one of Gaddafi's sons, Khamis.
In a co-ordinated revolt that rebel cells had been secretly preparing for months, shooting started last night across Tripoli, moments after Muslim clerics, using the loudspeakers on mosque minarets, called people on to the streets.
Gaddafi, in his second audio broadcast in 24 hours, dismissed the rebels as rats.
‘I am giving the order to open the weapons stockpiles,’ Gaddafi said. ‘I call on all Libyans to join this fight. Those who are afraid, give your weapons to your mothers or sisters.
‘Go out, I am with you until the end. I am in Tripoli. We will...win.’
If the Libyan leader is forced from power, there are question marks over whether the opposition can restore stability in this oil exporting country, as the rebels' own ranks have been wracked by disputes and rivalry.
